where \( \nu _{es}=D_{es}/h \) , fitting the data in Fig.REF c yields \( D_{es}=2.06 \pm 0.04 {\rm GHz} \) , \( E_{es}=93.1 \pm 23.3 {\rm MHz} \) , \( g_{es}=2.04 \pm 0.05 \)  , indicating that the angular momentum doesn’t play an important role in the ES at room temperature [1]}, [2]}, [3]}. Further verification of spin transitions in the ES was conducted by using the pulsed ODMR method. Before pulsed ODMR measurement, Rabi oscillation was measured to obtain MW \( \pi \) -pulse duration (Fig.REF a). In pulsed ODMR measurement, \( V_B^- \)  defects were initialized to \( m_S = 0 \)  state by optical pumping for 3 us, following a 1 us wait time to ensure spins had relaxed to the ground state. Then a \( \pi \) -pulse of 13 ns was applied to flip spin to \( m_S = -1 \)  state. After that, another laser pulse was applied to read out \( I_{\rm {PL}} \) . One can find that the broad peaks are not visible in pulsed ODMR spectrum while the GS transitions remain observable (Fig.REF b), which confirms that the broad peaks near 2.1 GHz do come from the excited state.
